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The upstream tunnel for Yellow River Crossing Project completed

Updated: 2009-12-25

On 10 am, Dec 22, the upstream tunnel for Yellow River Crossing Project of Middle Line of South-north Water Transfer Project, the grandest river-crossing project undertaken by CGGC, was finished, marking an unprecedented move in mankind’s history of crossing the Yellow River through an underground tunnel.

 

This picture shows the upstream tunnel.

The Yellow River Crossing project of the Middle Line of South-north Water Transfer Project is the most difficult part of the water diversion and requires the construction of largest-scale interchange structures. The two underground tunnels in the 19.3km-long project were the most eye-catching items. Each tunnel with a diameter of 7 meters is 4,250 meters long, consisting of 800m-long Mangshan part and 3,450m-long Yellow River crossing part. Employing the world-advanced shield tunneling technology, the joint team, formed by CGGC and China Railway Tunnel Group, assumed the phase I of the Yellow River Crossing Project.

Since the commencement in September 2005, the project department staff of the joint team has overcome numerous technical difficulties. They used milling connector to link the phase I and phase II slots of the double-wheel hydraulic milling machine introduced in the shaft construction, which was unprecedented at home and was listed into the 11th batch of Chinese enterprises’ new records; besides, the shielding machine was also used for the first time at home in the 50m-deep round shaft with high hydraulic pressure.